Abstract: The scientific application technology of pesticides to protect plant diseases and insect pests requires advanced application equipment ,high quality and correct pesticide and right application time．According, to different crops, stages of the crop, the pesticides should be applied with different application technologies in order to make full use of the chemical pesticides． The paper presents a whole set of new pesticide application technology to heighten the protective efficience, especially to protect the cotton from cotton bollworm injury．